From the introduction: Waterdeep’s glamorous Sea Ward. The festivities include a bustling outdoor holiday market and special performances at the CASSALANTER VILLA, which the Cassalanters have graciously opened to the public for the duration of the holiday. The pleasant atmosphere is tainted when aasimar opera singer, ARIA CAVATINA, is attacked by a tiny fiend that seemingly appears out of nowhere. The City Watch shuts down the event, holding guests in the villa for questioning until the culprit can be identified. The fiends wreaking havoc on the party are doing the bidding of ASMODEUS, who already holds sway over the Casslanters. The devils have been inadvertently summoned by young ELZERINA CASSALANTER, with whom Asmodeus has been communicating via her toys. Elzerina does not know that her innocent playtime has invited these devilish creatures into her home. Will characters be able to crack Asmodeus’s puzzle and put a stop to his fiendish meddling? With a villa full of Waterdeep’s most prominent citizens and a family with a secret so dark they’ll do anything to protect it, mayhem and mystery await this Midwinter!